Question

$A,B,C$ are three elements with the atomic number $Z-1,Z,Z+1$ respectively. $B$ is an inert gas. Which out of the three has positive electron gain enthalpy?

• A. $A$
• B. $B$
• C. $C$
• D. All of these

Answer 1

Answer: (B)

$B$

Elements: $A$ $B$ $C$

Atomic no.: $Z-1ZZ+1$

$B$ being an inert gas is very much stable hence the inclusion of new $e^{-}$ would require a high amount of energy as the outermost shell is already filled.

Hence, the electron gain enthalpy would be positive for B.